Thousands flee as 'gigantic' floodwaters threaten Bangkok

TENS of thousands of people jammed bus stations and highways to flee Thailand's capital as flood forecasts turned more grim and the first official evacuations were ordered.

Floodwaters bearing down on the metropolis of nine million people have killed 373 people nationwide since July, caused billions of dollars in damage and shut Bangkok's second largest airport.

The capital has mostly escaped unscathed, but residents are preparing for flooding that seems all but inevitable.

Bangkok Governor Sukhumbhand Paribatra said yesterday residents of two of the city's 50 districts - Don Muang and Bang Phlat, both already partially submerged - should leave for safer city shelters.

"This is the first time I am using the term 'evacuation', the first time I'm really asking you to leave," Mr Sukhumbhand said.

Elsewhere in the city, thousands of people packed Bangkok's Mo Chit bus terminal, trying to leave town on their own.

Many appeared to be taking advantage of a government-declared five-day public holiday to avoid a possible watery siege. The holiday runs from Thursday through to Monday in flood-affected areas, including Bangkok.

Some waited for hours on the sidewalk outside Mo Chit because there was no space inside the terminal, the main departure point for buses to Thailand's north.

The mass exodus included thousands of migrants from neighbouring Myanmar, workers dependent on low-paying jobs so desperate to leave they are willing to brave a return to their intensely repressive nation to do so.

Authorities were also forced to move hundreds of inmates from three prisons - many on death row - to facilities in other provinces.

Satellite maps of Bangkok showed a city almost entirely surrounded by water. Most of the vast pools of runoff now submerging a third of the country are flowing from the north toward Bangkok - southward toward the Gulf of Thailand.

"The amount of water is gigantic," Prime Minister Yingluck Shinawatra said.

"Some water must spread into Bangkok areas but we will try to make it pass through as quickly as possible."

In the district of Sai Mai, on the capital's northern outskirts, waist-high water turned roads into virtual rivers and swamped gas stations and homes.

Hundreds of residents clamoured aboard packed military trucks with their belongings, desperate to leave. But help was in short supply.

"We haven't been able to get on one (military truck) yet, we have been waiting for almost an hour," said 71-year-old Saman Somsuk. "There aren't many trucks."

Others got out any way they could - in paddle boats, plastic tubs, inner tubes and rubber rafts. Several men floated down a flooded road in a makeshift boat made of empty oil barrels tied to a rectangular plank.

As fears of urban disaster set in, some residents built cement walls to protect their shops and homes.

Websites posted instructions on the proper way to stack sandbags. Many residents fortified vulnerable areas of their houses with bricks, gypsum board and plastic sheets. Walls of sandbags or cinderblocks covered the entrances of many buildings.

Concern that pumps would fail prompted a run on plastic containers in which to hoard water. Anticipating worse, one woman travelling on Bangkok's Skytrain transit system carried a bag of life vests.

On Tuesday, floods breached barriers protecting the capital's Don Muang airport, primarily used for domestic flights, in a major psychological blow to efforts to protect the capital.

The country's main international airport is still functioning normally.

Panic has gripped parts of the city as more and more of it is affected by the advancing water. Residents stocking up on food and other necessities have emptied supermarket shelves, and stores have posted notices that flooding was disrupting supply chains and leaving them unable to restock certain items.

Yingluck warned that the city's fate rested on three key flood barriers.

"If the three spots ... remain intact, the situation will improve," she said. However, "in the worst case, if we can't protect all three spots, all of Bangkok will be flooded."

She has said the floods could range from 10cm to 1.5 metres deep in the capital.